This project investigates the role of phonological representations during high level language comprehension. The research tests the hypothesis that sustained activation of phonological information, interacting with semantic information, forms a crucial part of sentence and discourse comprehension. The approach builds on earlier work within a connectionist computational modeling framework in which linguistic working memory is not viewed as separate from the language comprehension system but rather as emergent from comprehension and production processes. A better understanding of the role of phonological information in memory and sentence comprehension will contribute to research on patients with phonological impairments and also to an understanding of language comprehension processes more generally. There are four specific aims: 1) Assess the role of phonological information in sentence processing in behavioral studies of normal readers. We hypothesize that phonological information has several distinct functions in sentence comprehension, including supplementing semantic information in maintaining distinct representations of discourse referents, and providing a verbatim representation of word order information to aid parsing of complex structures. 2) Use functional magnetic resonance imaging (fMRI) during sentence processing and working memory tasks to investigate the extent to which phonological activation contributes to sentence processing. 3) Investigate the memory and sentence processing abilities of patients with phonological impairments. 4) Develop computational models addressing the role of phonology in sentence comprehension in both normal and impaired populations.